Gogle App Script: Sort all rows with data (excluding header row), ascending, by two columns, taking two column header names in case the columns are rearranged.

Sort Google Sheet by two columns, 'Platform' and 'Team'.js

// This function gets column numbers by the header name
function getColumnNrByName(sheet, name) {
  var range = sheet.getRange(1, 1, 1, sheet.getMaxColumns());
  var values = range.getValues();
  
  for (var row in values) {
    for (var col in values[row]) {
      if (values[row][col] == name) {
        return parseInt(col);
      }
    }
  }
  
  throw 'failed to get column by name';
}

// This function sorts a Spreadsheet (the first sheet) by two columns named "Platform" and "Team", ascending, ignoring the header row
function sortSheet() {
  var ss = SpreadsheetApp.getActiveSpreadsheet(); // Get the current spreadsheet
  var sheet = ss.getSheets()[0]; // Get the first sheet
  var headerRowNumber = 1; // Define the header row number
  var range = sheet.getDataRange().offset(headerRowNumber, 0, sheet.getLastRow() - headerRowNumber); // get entire range of rows and columns that have data in them, excluding the header row
  var column_1 = getColumnNrByName(sheet, 'Platform') + 1; // Set the name of the 1st column to sort
  var column_2 = getColumnNrByName(sheet, 'Team') + 1; // Set the name of the 2nd column to sort

  range.sort([{column: column_1, ascending: true}, {column: column_2, ascending: true}]); // sort the range of data-filled cells by the two columns
}